E-book viewer: Add page flip animations. Their duration can be controlled via the viewer Preferences

src/calibre/gui2/viewer/config.ui

@@ -7,14 +7,14 @@
     <x>0</x>
     <y>0</y>
     <width>479</width>
-    <height>606</height>
+    <height>591</height>
    </rect>
   </property>
   <property name="windowTitle">
    <string>Configure Ebook viewer</string>
   </property>
   <property name="windowIcon">
-   <iconset>
+   <iconset resource="../../../../resources/images.qrc">
     <normaloff>:/images/config.png</normaloff>:/images/config.png</iconset>
   </property>
   <layout class="QGridLayout" name="gridLayout_4">
@@ -164,14 +164,14 @@
               </item>
              </widget>
             </item>
-            <item row="7" column="0" colspan="2">
+            <item row="8" column="0" colspan="2">
              <widget class="QCheckBox" name="opt_remember_window_size">
               <property name="text">
                <string>Remember last used &amp;window size</string>
               </property>
              </widget>
             </item>
-            <item row="8" column="0" colspan="2">
+            <item row="9" column="0" colspan="2">
              <widget class="QCheckBox" name="opt_remember_current_page">
               <property name="text">
                <string>Remember the &amp;current page when quitting</string>
@@ -201,21 +201,21 @@
               </property>
              </widget>
             </item>
-            <item row="4" column="0" colspan="2">
+            <item row="5" column="0" colspan="2">
              <widget class="QCheckBox" name="hyphenate">
               <property name="text">
                <string>H&amp;yphenate (break line in the middle of large words)</string>
               </property>
              </widget>
             </item>
-            <item row="5" column="1">
+            <item row="6" column="1">
              <widget class="QComboBox" name="hyphenate_default_lang">
               <property name="toolTip">
                <string>The default language to use for hyphenation rules. If the book does not specify a language, this will be used.</string>
               </property>
              </widget>
             </item>
-            <item row="5" column="0">
+            <item row="6" column="0">
              <widget class="QLabel" name="label_8">
               <property name="text">
                <string>Default &amp;language for hyphenation:</string>
@@ -225,30 +225,66 @@
               </property>
              </widget>
             </item>
-            <item row="6" column="0" colspan="2">
+            <item row="7" column="0" colspan="2">
              <widget class="QCheckBox" name="opt_fit_images">
               <property name="text">
                <string>&amp;Resize images larger than the viewer window (needs restart)</string>
               </property>
              </widget>
             </item>
+            <item row="4" column="0">
+             <widget class="QLabel" name="label_11">
+              <property name="text">
+               <string>Page flip &amp;duration:</string>
+              </property>
+              <property name="buddy">
+               <cstring>opt_page_flip_duration</cstring>
+              </property>
+             </widget>
+            </item>
+            <item row="4" column="1">
+             <widget class="QDoubleSpinBox" name="opt_page_flip_duration">
+              <property name="specialValueText">
+               <string>disabled</string>
+              </property>
+              <property name="suffix">
+               <string> secs</string>
+              </property>
+              <property name="decimals">
+               <number>1</number>
+              </property>
+              <property name="minimum">
+               <double>0.100000000000000</double>
+              </property>
+              <property name="maximum">
+               <double>3.000000000000000</double>
+              </property>
+              <property name="singleStep">
+               <double>0.100000000000000</double>
+              </property>
+              <property name="value">
+               <double>0.500000000000000</double>
+              </property>
+             </widget>
+            </item>
            </layout>
           </item>
-          <item row="3" column="0">
-           <widget class="QGroupBox" name="groupBox_2">
-            <property name="title">
-             <string>&amp;User stylesheet</string>
-            </property>
-            <layout class="QGridLayout" name="gridLayout_5">
-             <item row="1" column="0">
-              <widget class="QPlainTextEdit" name="css"/>
-             </item>
-            </layout>
-           </widget>
-          </item>
          </layout>
         </widget>
        </item>
+       <item>
+        <spacer name="verticalSpacer">
+         <property name="orientation">
+          <enum>Qt::Vertical</enum>
+         </property>
+         <property name="sizeHint" stdset="0">
+          <size>
+           <width>20</width>
+           <height>40</height>
+          </size>
+         </property>
+        </spacer>
+       </item>
       </layout>
      </widget>
      <widget class="QWidget" name="tab_2">
@@ -268,6 +304,29 @@
        </item>
       </layout>
      </widget>
+     <widget class="QWidget" name="tab_3">
+      <attribute name="title">
+       <string>User &amp;Stylesheet</string>
+      </attribute>
+      <layout class="QVBoxLayout" name="verticalLayout_3">
+       <item>
+        <widget class="QLabel" name="label_10">
+         <property name="text">
+          <string>&lt;p&gt;A CSS stylesheet that can be used to control the look and feel of books. For examples, click &lt;a href=&quot;http://www.mobileread.com/forums/showthread.php?t=51500&quot;&gt;here&lt;/a&gt;.</string>
+         </property>
+         <property name="wordWrap">
+          <bool>true</bool>
+         </property>
+         <property name="openExternalLinks">
+          <bool>true</bool>
+         </property>
+        </widget>
+       </item>
+       <item>
+        <widget class="QPlainTextEdit" name="css"/>
+       </item>
+      </layout>
+     </widget>
     </widget>
    </item>
   </layout>
@@ -281,7 +340,6 @@
   <tabstop>standard_font</tabstop>
   <tabstop>max_view_width</tabstop>
   <tabstop>opt_remember_window_size</tabstop>
-  <tabstop>css</tabstop>
   <tabstop>buttonBox</tabstop>
  </tabstops>
  <resources>

src/calibre/gui2/viewer/documentview.py

@@ -18,6 +18,7 @@ from PyQt4.QtWebKit import QWebPage, QWebView, QWebSettings
 from calibre.utils.config import Config, StringConfig
 from calibre.utils.localization import get_language
 from calibre.gui2.viewer.config_ui import Ui_Dialog
+from calibre.gui2.viewer.flip import SlideFlip
 from calibre.gui2.shortcuts import Shortcuts, ShortcutConfig
 from calibre.constants import iswindows
 from calibre import prints, guess_type
@@ -52,6 +53,9 @@ def config(defaults=None):
             help=_('Default language for hyphenation rules'))
     c.add_opt('remember_current_page', default=True,
             help=_('Save the current position in the document, when quitting'))
+    c.add_opt('page_flip_duration', default=0.5,
+            help=_('The time, in seconds, for the page flip animation. Default'
+                ' is half a second.'))
 
     fonts = c.add_group('FONTS', _('Font options'))
     fonts('serif_family', default='Times New Roman' if iswindows else 'Liberation Serif',
@@ -75,6 +79,7 @@ class ConfigDialog(QDialog, Ui_Dialog):
         opts = config().parse()
         self.opt_remember_window_size.setChecked(opts.remember_window_size)
         self.opt_remember_current_page.setChecked(opts.remember_current_page)
+        self.opt_page_flip_duration.setValue(opts.page_flip_duration)
         self.serif_family.setCurrentFont(QFont(opts.serif_family))
         self.sans_family.setCurrentFont(QFont(opts.sans_family))
         self.mono_family.setCurrentFont(QFont(opts.mono_family))
@@ -122,6 +127,7 @@ class ConfigDialog(QDialog, Ui_Dialog):
         c.set('max_view_width', int(self.max_view_width.value()))
         c.set('hyphenate', self.hyphenate.isChecked())
         c.set('remember_current_page', self.opt_remember_current_page.isChecked())
+        c.set('page_flip_duration', self.opt_page_flip_duration.value())
         idx = self.hyphenate_default_lang.currentIndex()
         c.set('hyphenate_default_lang',
                 str(self.hyphenate_default_lang.itemData(idx).toString()))
@@ -197,6 +203,8 @@ class Document(QWebPage):
         self.hyphenate = opts.hyphenate
         self.hyphenate_default_lang = opts.hyphenate_default_lang
         self.do_fit_images = opts.fit_images
+        self.page_flip_duration = opts.page_flip_duration
+        self.enable_page_flip = self.page_flip_duration > 0.1
 
     def fit_images(self):
         if self.do_fit_images:
@@ -453,6 +461,7 @@ class DocumentView(QWebView):
 
     def __init__(self, *args):
         QWebView.__init__(self, *args)
+        self.flipper = SlideFlip(self)
         self.debug_javascript = False
         self.shortcuts =  Shortcuts(SHORTCUTS, 'shortcuts/viewer')
         self.self_closing_pat = re.compile(r'<([a-z1-6]+)\s+([^>]+)/>',
@@ -708,12 +717,17 @@ class DocumentView(QWebView):
                 return False
         return True
 
-    def find_next_blank_line(self, overlap):
+    def current_page_image(self, overlap=-1):
+        if overlap < 0:
+            overlap = self.height()
         img = QImage(self.width(), overlap, QImage.Format_ARGB32)
         painter = QPainter(img)
-        # Render a region of width x overlap pixels atthe bottom of the current viewport
         self.document.mainFrame().render(painter, QRegion(0, 0, self.width(), overlap))
         painter.end()
+        return img
+
+    def find_next_blank_line(self, overlap):
+        img = self.current_page_image(overlap)
         for i in range(overlap-1, -1, -1):
             if self.test_line(img, i):
                 self.scroll_by(y=i, notify=False)
@@ -721,6 +735,10 @@ class DocumentView(QWebView):
         self.scroll_by(y=overlap)
 
     def previous_page(self):
+        if self.flipper.running:
+            return
+        epf = self.document.enable_page_flip
+
         delta_y = self.document.window_height - 25
         if self.document.at_top:
             if self.manager is not None:
@@ -732,11 +750,20 @@ class DocumentView(QWebView):
             if upper_limit < 0:
                 upper_limit = 0
             if upper_limit < opos:
+                if epf:
+                    self.flipper.initialize(self.current_page_image())
                 self.document.scroll_to(self.document.xpos, upper_limit)
+                if epf:
+                    self.flipper(self.current_page_image(), forwards=False,
+                            duration=self.document.page_flip_duration)
             if self.manager is not None:
                 self.manager.scrolled(self.scroll_fraction)
 
     def next_page(self):
+        if self.flipper.running:
+            return
+        epf = self.document.enable_page_flip
+
         window_height = self.document.window_height
         document_height = self.document.height
         ddelta = document_height - window_height
@@ -770,6 +797,10 @@ class DocumentView(QWebView):
                     return
                 #print 'Setting padding to:', lower_limit - max_y
                 self.document.set_bottom_padding(lower_limit - max_y)
+            before_img = None
+            if epf:
+                before_img = self.current_page_image()
+                self.flipper.initialize(before_img)
             #print 'Document height:', self.document.height
             max_y = self.document.height - window_height
             lower_limit = min(max_y, lower_limit)
@@ -780,6 +811,9 @@ class DocumentView(QWebView):
             #print 'After scroll pos:', self.document.ypos
             self.find_next_blank_line(window_height - actually_scrolled)
             #print 'After blank line pos:', self.document.ypos
+            if epf:
+                self.flipper(self.current_page_image(),
+                        duration=self.document.page_flip_duration)
             if self.manager is not None:
                 self.manager.scrolled(self.scroll_fraction)
             #print 'After all:', self.document.ypos

src/calibre/gui2/viewer/flip.py

@@ -0,0 +1,94 @@
+#!/usr/bin/env python
+# vim:fileencoding=UTF-8:ts=4:sw=4:sta:et:sts=4:ai
+
+__license__   = 'GPL v3'
+__copyright__ = '2010, Kovid Goyal <kovid@kovidgoyal.net>'
+__docformat__ = 'restructuredtext en'
+
+from PyQt4.Qt import QWidget, QPainter, QPropertyAnimation, QEasingCurve, \
+    QRect, QPixmap, Qt, pyqtProperty
+
+class SlideFlip(QWidget):
+
+    def __init__(self, parent):
+        QWidget.__init__(self, parent)
+
+        self.setGeometry(0, 0, 1, 1)
+        self._current_width = 0
+        self.before_image = self.after_image = None
+        self.animation = QPropertyAnimation(self, 'current_width', self)
+        self.setVisible(False)
+        self.animation.valueChanged.connect(self.update)
+        self.animation.finished.connect(self.finished)
+        self.flip_forwards = True
+        self.setAttribute(Qt.WA_OpaquePaintEvent)
+
+    @property
+    def running(self):
+        return self.animation.state() == self.animation.Running
+
+    def initialize(self, image):
+        self.before_image = QPixmap.fromImage(image)
+        self.after_image = None
+        self.setGeometry(0, 0, image.width(), image.height())
+        self.setVisible(True)
+
+    def __call__(self, image, duration=0.5, forwards=True):
+        if self.running:
+            return
+        self.flip_forwards = forwards
+        self.after_image = QPixmap.fromImage(image)
+
+        if self.flip_forwards:
+            self.animation.setStartValue(image.width())
+            self.animation.setEndValue(0)
+            t = self.before_image
+            self.before_image = self.after_image
+            self.after_image = t
+            self.animation.setEasingCurve(QEasingCurve(QEasingCurve.InExpo))
+        else:
+            self.animation.setStartValue(0)
+            self.animation.setEndValue(image.width())
+            self.animation.setEasingCurve(QEasingCurve(QEasingCurve.OutExpo))
+
+        self.animation.setDuration(duration * 1000)
+        self.animation.start()
+
+    def finished(self):
+        self.setVisible(False)
+        self.before_image = self.after_image = None
+
+    def paintEvent(self, ev):
+        if self.before_image is None:
+            return
+        canvas_size = self.rect()
+        p = QPainter(self)
+        p.setRenderHints(QPainter.Antialiasing | QPainter.SmoothPixmapTransform)
+
+        p.drawPixmap(canvas_size, self.before_image,
+                    self.before_image.rect())
+        if self.after_image is not None:
+            width = self._current_width
+            iw = self.after_image.width()
+            sh = min(self.after_image.height(), canvas_size.height())
+
+            if self.flip_forwards:
+                source = QRect(max(0, iw - width), 0, width, sh)
+            else:
+                source = QRect(0, 0, width, sh)
+
+            target = QRect(source)
+            target.moveLeft(0)
+            p.drawPixmap(target, self.after_image, source)
+
+        p.end()
+
+    def set_current_width(self, val):
+        self._current_width = val
+
+    current_width = pyqtProperty('int',
+            fget=lambda self: self._current_width,
+            fset=set_current_width
+            )
+
+